1. Field of the Invention
The present invention relates to improvement of a semiconductor integrated circuit apparatus having electronic parts such as semiconductor integrated circuit devices and a cooling apparatus for the electronic parts on a board.
2. Description of the Related Art
FIG. 11 is a cross-sectional view showing an example of a conventional semiconductor integrated circuit apparatus having an electronic part such as a semiconductor integrated circuit device and a cooling apparatus for the electronic part on a board. As shown in FIG. 11, heretofore, when a cooling member such as a heat sink fin 3 is attached to an electronic part 1 mounted on a board 2, an adhesive 8 is used for bonding. However, this method has a possibility that, if the heat sink fin 3 is detached from the electronic part 1, both parts may be broken. In addition, if the heat sink fin 3 is fixed on the board with screws (for example, Japanese Patent Laid-Open No. 5-243439), it is possible to detach the heat sink fin 3 from the electronic part 1 without damage by removing these screws. However, in case of using screws, tapped holes should be prepared in the board 2, and consequently this causes a problem that parts mounting density on the board is reduced by these tapped holes.
In order to solve these problems, recently, a constitution has been proposed in which a heat sink fin is attached through thermally-conductive fats and fatty oils such as a thermally-conductive grease or a thermally-conductive resin on the upper face of a semiconductor package, and this heat sink fin is compressed with springs that are attached under a fixed plate fixed on the board (for example, Japanese Patent Laid-Open No. 5-82688).
However, in the conventional semiconductor integrated circuit apparatus as described above, since a fixed plate supports a heat sink fin from four directions and an upper direction, a fixed plate can be used only for a heat sink fin having a size corresponding to the fixed plate. In general, the sizes of electronic parts such as a semiconductor package and heat sink fin corresponding to it, in particular, the sizes in the direction parallel to a board are various. Therefore, this causes problems that, if a heat sink fin is changed to a new one in different size, there may be no fixed plate suitable to the new heat sink fin, and, even if the suitable fixed plate is available, time is wasted in searching for and exchanging plates.
In addition, there are electronic parts and heat sink fins of various sizes not only parallel to but also perpendicular to a board. However, in a conventional semiconductor integrated circuit apparatus, it is very difficult flexiblely to respond to size changes of electronic parts in the these directions.
Further, in a conventional semiconductor integrated circuit apparatus, it is difficult to radiate sufficient heat from electronic parts efficiently.
Furthermore, in conventional semiconductor integrated circuit apparatus, it is not possible sufficiently to respond to a plurality of electronic parts having significantly different heights, with one cooling member.